Answer: 0.16
Step-by-step explanation:
Given that the run times provided are normally distributed ;
Mean(x) of distribution = 3 hours 50 minutes
Standard deviation(s) = 30 minutes
The probability that a randomly selected runner has a time less than or equal to 3 hours 20 minutes
3 hours 20 minutes = (3 hrs 50 mins - 30 mins):
This is equivalent to :
[mean(x) - 1 standard deviation]
z 1 standard deviation within the mean = 0.84
z, 1 standard deviation outside the mean equals:
P(1 - z value , 1standard deviation within the mean)
1 - 0.8413 = 0.1587
= 0.16
Answer: (x,y) = (-1, 1)
This means that x = -1 and y = 1
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Explanation:
The first equation says that y is the same as 2x+3
That allows us to substitute y for 2x+3 in the second equation like so:
2x+5y = 3
2x+5( y ) = 3
2x + 5(2x+3) = 3 .... y replaced with 2x+3
2x+10x+15 = 3
12x+15 = 3
12x = 3-15
12x = -12
x = -12/12
x = -1
Then we'll substitute this into the first equation to find y
y = 2x+3
y = 2(-1) + 3 .... x replaced with -1
y = -2+3
y = 1
Together x = -1 and y = 1 pair up to form the ordered pair solution (x,y) = (-1,1)
If you were to graph y = 2x+3 and 2x+5y=3 on the same xy grid, then you should see that the two lines intersect at the location (-1,1). This is a visual way to determine the solution quickly through use of a graphing calculator.
The answer is $212.37 for each large flatscreen tv
Answer:
a(n) = -16b + (n - 1)(3b)
Step-by-step explanation:
First term is -6b.
Common difference is 3b; each new term is equal to the previous one, plus 3b.
Formula for this arithmetic sequence is
a(n) = -16b + (n - 1)(3b)
Answer:
y=-5,x=2
Step-by-step explanation:
3x+3y=-9________________eqn 1
3x-3y=21________________eqn 2
using elimination method
3x+3y=-9
-
3x-3y=21
subtract equation 2 from equation 1
0+6y=-30
6y=-30
y=-30/6
y=-5
substitute the value of y in equation 1
3x+3y=-9
3x+3(-5)=-9
3x-15=-9
3x=-9+15
3x=6
x=6/3
x=2
